This invention relates to barriers for mounting along a roof to restrain snow and ice from sliding off the roof. More particularly, it relates to mechanical designs and methods of installation of such devices.
Snow barriers are well established as a necessary accessory for roofs in northern climates. Such devices should be easy to install, anchor reliably, and be capable of retaining a substantial mass of snow. The design of such devices must address maximum, extreme conditions.
Typical prior art designs for snow barrier have employed tubing fitted through roof-mounted brackets. Such brackets have been individually mounted to the roof surface. Arrangements of this type are labourious to install and are difficult to align precisely.
A need exists for a more convenient methodology for installing snow barrier and associated hardware, that is of reasonable cost. The present invention addresses that objective.
The invention in its general form will first be described, and then its implementation in terms of specific embodiments will be detailed with reference to the drawings following hereafter. These embodiments are intended to demonstrate the principle of the invention, and the manner of its implementation. The invention in its broadest and more specific forms will then be further described, and defined, in each of the individual claims which conclude this Specification.
According to the invention in one aspect a snow barrier comprises a support bracket that slidably engages with a track. The track is mounted to the surface of a roof, preferably in the case of metal roofs, at a seam. Once the bracket has been slid to a correct location on the track, it is fastened in position and a fence installed, spanning between the brackets. As a track has a longer length than a bracket, it is easier to locate it over appropriate anchor points.
The brackets may have two legs, each with surfaces shaped to slidingly interfit within the track, but each leg having differing lengths. This provides the option of mounting the brackets to support fence attachments of differing heights and strengths on an upright leg of corresponding height.
A fence may be provided in the form of tubular rails that pass through the brackets. Preferably, the fence may be formed of corrugated sheet metal strips that are fastened to the up-slope face of the upright leg of the brackets. This corrugated sheet metal can be in a single sheet. Alternately, it may be modular in form, comprising lengths of single corrugations that are xe2x80x9cUxe2x80x9d-shaped in cross-section. These modular strips can be assembled to form a fence with multiple corrugations of selectable height and strengths.
The differing lengths of legs may be fitted with one, two or more corrugation elements.
Optionally, the brackets may also be perforated to receive and support tubular rails as well as being adapted to receive a corrugated fence. Such perforations may be along both legs of each bracket, inwardly from the outer edges of the legs of the brackets. The bracket legs may contain differing numbers of perforations along their respective legs to receive differing numbers of tubes. In this manner, a fence of differing heights and strengths may be installed.
An advantage of having the brackets installed to slide in tracks is that alignment is simplified. With a fence attached to the front face of the upright legs of two separated brackets, the remaining, intervening brackets may be slid up their respective tracks into position for attachment to the fence. Alignment is automatic.
The installation process is also enhanced by the feature of shaping the top edge of the corrugated fence with a hooked flange that will engage, and hook-over, the top end of a bracket. This ensures that the corrugated fence is in position at the correct height when it is attached. Attachment may be effected by any attachment means, such as screws. Each modular corrugation strip may also be provided with a reversely-bent bottom flange that will receive the hooked flange formed on the upper edge of a further corrugation strip positioned directly below.
As well as providing ease of alignment, the tracks may be dimensioned to extend both up-slope along the roof, above the fence line and down-slope. This allows the tracks to be preferably anchored to transverse stringers within the roof or other structural features of the roof that are not directly below the fence line. By extending the tracks up-roof, not only is the option of accessing a suitable anchor-point provided, but also, the lever-arm of the track in resisting the overturning of the fence by a heavy snow load is extended. This allows for a stronger construction and/or cost-saving adjustments in other components, such as the use of lower cost fasteners for attachment to the roof.
The features of the invention need not always incorporate a track mount. Optionally, brackets may be mounted directly on a roof, partially or entirely supported on pads of expanded width to distribute the forces applied to a roof when the snow barrier is placed under load.
By these features, and by the combination of these features a new and improved snow fence system can be provided.
The foregoing summarizes the principal features of the invention and some of its optional aspects. The invention may be further understood by the description of the preferred embodiments, in conjunction with the drawings, which now follow.